Scientists at the Centre for Nano and Soft Matter Sciences (CeNS), Bengaluru, an autonomous institute under the Department of Science and Technology (DST), have developed an advanced ammonia sensor capable of detecting toxic gas at extremely low concentrations while operating efficiently at room temperature.
The breakthrough technology is expected to improve workplace safety, environmental monitoring and public health by enabling portable, self-powered and wearable devices that can detect hazardous ammonia leaks in real time.
Ammonia is widely used in industries such as fertiliser manufacturing, refrigeration, chemical production and agriculture. However, accidental exposure to the gas can cause severe irritation to the eyes, skin and respiratory system, while prolonged exposure may result in serious health complications, making continuous monitoring essential.
The CeNS research team developed the sensor using a hybrid vanadium oxide-vanadium sulfide (VOx/VS₂) heterostructure, engineered through a controlled surface transformation process. The design creates abundant active sites for ammonia adsorption while enhancing charge transport, significantly improving the sensor’s sensitivity and selectivity.
The newly developed sensor can detect ammonia concentrations as low as 319 parts per billion (ppb), well below occupational safety limits. It also demonstrated excellent selectivity against other common gases, stable performance over repeated sensing cycles, long-term reliability exceeding ten weeks, and effective operation across a wide range of ammonia concentrations.
Unlike conventional gas sensors that require high operating temperatures or external activation, the new device functions at room temperature, reducing energy consumption and making it easier to deploy in real-world environments.
Led by Prof. Angappane Subramanian, along with Dr. Vishnu G. Nath, Ankur Verma, Abhijit Paul, and Dr. Subash Cherumannil Karumuthil, the research team translated the laboratory innovation into practical prototypes for industrial and consumer applications.
Among the prototypes developed is a portable threshold-triggered monitoring device that automatically classifies ammonia levels into safe, warning and danger zones, enabling users to respond quickly without technical expertise. The system is designed for use in industrial plants, storage facilities, laboratories and agricultural settings where ammonia leakage poses a significant risk.
The researchers also developed a self-powered ammonia sensor by integrating the sensing platform with a flexible piezoelectric nanogenerator. The device harvests energy generated from simple human movements to power itself, eliminating the need for an external power source and making it suitable for remote or resource-constrained locations.
In addition, the team fabricated flexible and wearable versions of the sensor on polymer, paper and textile substrates. The lightweight devices retained their sensing capabilities even when bent, twisted or folded, demonstrating their potential for wearable electronics.
To showcase practical applications, the researchers developed prototype smart bands, smart-home warning systems and electronic textile platforms designed for personal safety monitoring and intelligent environmental sensing.
The findings, published in the journal ACS Sensors, highlight how advanced nanomaterials and innovative device engineering can be combined to create next-generation gas monitoring technologies. The successful demonstration of portable, wearable and self-powered sensor prototypes marks a significant step toward improving toxic gas detection and enhancing safety across industrial, environmental and public health settings.
